1. Field of the Invention
The present invention relates to a silk screen frame emulsion coating apparatus. More particularly the apparatus is completely electro-mechanical requiring no hydraulics or pneumatics and further includes a sensor system for detecting warpage in a screen and adjusting trough position to accommodate the warpage.
2. Description of the Prior Art
Heretofore various emulsion coating apparatus have been proposed. They range from manual to highly sophisticated. Examples are disclosed in the following U.S. Patents:
______________________________________ U.S. Pat. No. Patentee ______________________________________ 4,363,289 Gasser 4,599,249 Shirataki 4,668,329 Shirataki 5,093,160 Johnson et al. ______________________________________
All the prior art apparatus include hydraulics for use in moving movable elements of the apparatus. Such hydraulics make the apparatus sensitive to ambient conditions, creating a drawback in the necessity of an appropriate environment.
Further, none of the prior art can accommodate for warpage in a screen to be coated. Such warpage is commonly encountered and inherently decreases the quality of a coating applied to the warped area.
The stencil emulsion coating directly influences image reproduction quality of the resulting silk screen print.
As will be described in greater detail hereinafter, the apparatus of the present invention is entirely electro-mechanical and does not utilize hydraulics or pneumatics. This makes the apparatus very reliable and allows the apparatus to be worked in environments unsuitable for hydraulic/pneumatics actuators. Further, because of mechanical simplicity, the apparatus herein disclosed is much less expensive to manufacture. Also, as will be defined in greater detail hereinafter, a sensing system is provided for detecting areas of screen warpage and accommodating for same providing a significantly increased percentage of useable screens, saving time and labor.